Sofa bed



FIG. 1 is a Perspective view of a sofa bed showing my new design;

FIG. 2 is a Front view thereof;

FIG. 3 is a Back view thereof;

FIG. 4 is a Right-side view thereof;

FIG. 5 is a left-side view thereof;

FIG. 6 is a Top view thereof;

FIG. 7 is a Bottom view thereof;

FIG. 8 is other Perspective view of a sofa bed showing in my new design;

FIG. 9 is a Left-side view of the sofa bed as shown in FIG. 8 ;

FIG. 10 is a Top view of the sofa bed as shown in FIG. 8 ; and,

FIG. 11 is a Front view of the sofa bed as shown in FIG. 8 .

The broken lines in the drawings depict portions of the sofa bed that form no part of the claimed design. 

CLAIM I claim the ornamental design for a sofa bed, as shown and described. 